网络化虚拟仪器的设计与实现

本文介绍了虚拟仪器的网络化技术,提出了网络化虚拟仪器的设计思想,并对虚拟仪器网络化的软件开发方法做了阐述.文中指出,在组建虚拟仪器网络测试系统时,有多种技术和方法可供选择.     

现代测试技术实验平台研究

将计算机网络、虚拟仪器、测控技术和LabWindows/CVI编程技术等有机结合,用PC机与各种虚拟仪器构成网络连接,设计出基于网络化测控技术和虚拟仪器技术的现代测试技术实验平台,并在此基础上构建出基于Internet和GPIB总线的网络化电子测量和控制实验室,并实现对各种虚拟仪器的远程控制.该技术在我校的网络化电子测量和控制实验室已经实际应用.     

车辆综合性能网络化虚拟仪器测试系统

针对传统仪器在车辆综合性能测试中存在的不足，将虚拟仪器技术引入车辆性能测试领域，并利用DataSocket、Web Sever通信技术开发了车辆综合性能网络化虚拟仪器测试系统．该测试系统采用PC—DAQ方案及串口通讯等，通过多传感器采集和数据融合，配以虚拟仪器测控软件，实现时汽车底盘测功、排放、噪声、侧滑、前照灯、制动以及悬架特性等性能进行测试的网络化测试仪器系统．实践表明，虚拟仪器及其网络化技术的应用提高了数据采集测控系统的性能，增强了信息、数据共享功能，系统具有实时性、可扩展性和准确可靠等优点．     

网络化虚拟仪器技术的现状与研究方向

介绍了网络化虚拟仪器技术的概念及应用前景,阐述了构成网络化虚拟仪器的客户／服务器、浏览器／服务器、客户／服务器／浏览器3种结构模式。重点讨论了网络化虚拟仪器的实现方式,并探讨了网络化虚拟仪器的研究方向,最后指出网络技术应用到虚拟仪器领域是虚拟仪器发展的必然趋势。     

基于虚拟仪器的数据传输系统的设计

虚拟仪器的网络化数据传输系统主要利用Labview软件及其网络化数据采集技术在计算机网络中多台计算机间实行数据实时传输和发布。通过对Labview软件实现计算机网络数据传输方法的比较分析,总结出基于虚拟仪器的计算机网络化数据传输系统的总体设计方法。     

网络化测控技术中同步技术研究

时间同步是网络化测试技术的关键问题之一。本文根据网络化测试系统的体系结构和特点,系统分析了三种常用的网络同步技术的机制和特点,分析对比了IEEE 1588、NTP和GPS各自的优缺点,从而可以根据网络化测试系统的特点选取不同的同步技术。     

分布式实时在线监测系统在产品安全检测中的应用

虚拟仪器是基于计算机的仪器,其应用和研究是计算机应用研究的热点.异地检测是产品安全检测实验室亟需面对和解决的问题,网络化虚拟仪器的应用成为必要和可行.论文应用LabVIEW开发了远程控制虚拟仪器的分布式实时在线监测系统,介绍了该系统的体系结构,系统设计以及关键技术,实现了异地控制虚拟仪器测试,为虚拟仪器测试的网络化提供了较高的参考价值.系统采用了底层编程技术屏蔽了底层接口的多样性以及多线程技术的采用,保证了系统运行的可移植、稳定、可靠和高效.实验表明,该系统能够成功地进行本地检测和异地检测.     

网络虚拟仪器的开发研究

介绍了网络化虚拟仪器的基本概念,提出了一套基于.net框架下的Web网络化虚拟仪器的解决方案:采用.net组件技术构造用户界面组件、数据服务组件、信号分析组件、数据库服务组件和采集控制组件,根据需要,将上述组件灵活地部署到合适的位置,实现远程测试.按照这种解决方案设计了一套基于Web的网络化示波器,可以进行远端数据采集.并将数据库技术引入网络化虚拟仪器中,实现对信号的存取管理功能.     

基于IP接口技术的测控仪器网络化实现

在探讨虚拟仪器技术、嵌入式测控系统、网络数据传输器和单片机加网络芯片等实现网络化仪器几种方法的关键技术,阐述网络化测控仪器的一般结构和基于B/S网络模式的测控系统的实现技术的基础上,提出了网络化仪器在实际应用中根据目标的需求而采用的不同实现方法.解决了开发IP接口技术测控仪器的各种问题,并通过实验证明了各种方法的可行性和有效性.指出科学仪器网络化是未来仪器发展的必然方向.     

网络化虚拟仪器实验室监控平台系统的开发

本文通过研究目前社会流行的网络化虚拟仪器监控平台技术,开发了网络化虚拟仪器实验室监控平台系统,编制相应界面显示主机的各类界面信息,通过Web技术和以太网通信方式,在实验室网络环境向用户发布监控主机工作页面信息。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that